html,head,body,div,p,ul,li,ol,a,input,form,i,b,img,span,button,em{
    margin: 0;
    padding: 0;
}
li{
    list-style-type: none;
}
a{
    text-decoration-line: none;
}
#my_home{
	position: relative;
}
#my_home > a:hover ~ i{
	display: block;
}
#my_home > i:hover{
	display: block;
}
#my_home > i{
	width: 120px;
	height: 30px;
	font-size: 12px;
	display: none;
	position: absolute;
	top: 100%;
	left: -20px;
	padding-top: 10px;
	border: 1px solid black;
	background: black;
}
/* 为空 */
.null_div{
	width: 100%;
	height: 200px;
	text-align: center;
	font-weight: 400px;
}